Gaspare appears to have been born to a Genoese merchant living in Naples. He appears to have been baptized on February 15, 1722, in the church of Santa maria dellIncoronatella in Naples under the name Gasparro Giovanni Battista Pascale Traversa. He trained under Francesco Solimena. He was a contemporary of other Solimena pupils, Giuseppe Bonito (1707–1789), also a genre painter, and Francesco de Mura (1696–1784). He was active mainly between 1732–1769.
Traversi can be described as a Neapolitan Hogarth, Steen or Longhi, working in a Caravaggist style. Traversis satirical paintings typically depict animated groups of bourgeois protagonists that seem compressed physically into an indoor pictorial space that can barely contain them. Even his religious canvases have foreshortened crowding. Facial expressions are lively and varied; some of the characters, often children, stare at the viewer. Women are often situated in either a foolish or ironic situation, or engage in a pulchritudinous talent, while men leer or participate with other intentions in mind. One could view these as elaborations of moralistic tales, such as Caravaggios The Fortune Teller, a topic which Traversi also depicted, but Traversis living rooms are more densely populated, and the emotions, as well as the situations, teeter awkwardly with imbalance.